A turret firing.
Turret fire exploding as it hits a tank.
Guns being used in a military ceremony.
Guns are weapons used in Civilization Stage that fire small kinetic or explosive bullets at their target. These bullets travel at a very high speed, making them seem nearly as fast as lasers and faster than blasters, the two weapons that replace them in Space Stage. When a Civilization Stage planet is visited, this style of turret will still be used, although they will not fire on the player's spaceship unless provoked (by dropping bombs on the city, for example). They cause rapid damage to a player's spaceship, almost as high as that received from a thundercloud on a T0 planet with a dense atmosphere.
The "Machine Gun Fire" and "Machine Gun Impact" Effects in Spore Galactic Adventures mimic the appearance of rapid gunfire and bullets deflecting off a surface respectively. Like all Effects, however, the bullets do not affect anything physically.
Turret Guns[]
Turrets in Civilization Stage use rapid-fire machine guns. The bullets from these turrets are capable of destroying all but heavily-armoured enemy vehicles within several seconds. They are very precise weapons, capable of shooting down aircraft around a hundred metres up in the sky from the turrets. Military land and sea vehicles also fire a similar weapon as an anti-aircraft defence.
Some of the bullets seem to explode when they hit their target, suggesting that the guns may make use of explosive shells. This would mean that they are actually autocannon, which would probably be a more likely choice for a weapon designed to destroy armoured vehicles.
Although guns are not used by Space Stage empires, their turrets often fire unguided explosive projectiles as anti-spaceship flak weapons, similar to the explosive shells of the earlier gun turrets.
Hand-held guns[]
During certain ceremonies in military cities, hand-held guns are fired into the air. The bullets fired by these (if they actually fire any bullets) do not appear to be explosive, so the guns are probably normal rifles. They are most likely doing a 5-gun salute. These weapons are never used in combat, probably because they would be worthless against the armour all vehicles are protected by.